Lets say you have 2 GPU's (or even 3way or quad) but you are just reading this forum.
Any one working GPU would be more than enough for surfing the web or write e-mails etc.
But those other "useless" GPU's consume a lot of power even in idle, can they be powered down?
 
In case of 3way SLI by 8800Ultra's this means an incredible 2x185W=370W is wasted.  
If this is already possible and what hardware or software would be needed?
This seems better for the enviroment, cooling and our wallets    
 
I hope this is not a pointless thread but I never read anything about this issue.

Generally those with 3 x 8800 Ultras have too much money to care about the electricity used, and probably drive big 4 X 4's with huge emissions.  
 
If they can afford it, they'll do it. Simple as that.  
 
I however try and keep my carbon footprint to a minimum. Wolfdale chip

v nice way of putting it dev1se think that would be the least of peoples worries  with sli setups etc

I did some googling and I found there will be some hybrid solutions providing this.
 
The onboard VGA chip will do all the work and an extra (optional) pcie card can help when gaming etc but would be powered down when not needed.  
 
It would be nice to implement this in all SLI configs.

Why not use ATITool or Rivatuner to underclock your card while in 2D?  You can save it as a profile and and come back to it when you're done gaming.

How much power will you save by underclocking VS "shutting it off completly"...AKA pulling it out of your system?

 
Hey now, I bet a 4x4 old Hummer burns cleaner then a old honda civic....besides the 4x4's cool factor far outweighs its MPG.
 
BTW I believe there is a setting in Vista under the power management to decrease the PCI-E voltage during Idle...But I'm not sure how well or effective that option is.

Ok I agree the whole discussion if you afford those cards pay the electricity, but it's just so pointless. I'd consider buying these cards but if in addition I'll get a huge electricity bill they are really expensive. I'll only use the pc about half the time for gaming it seems such a waste.  
I wonder what would happen if you pull the power of SLI, will the system still work without new settings/reboot? Maybe there is a way to put a switch on the power? But I guess you would allso have to pull the card out of the pcie slot ... mhhh... :-(

ATI Hybrid CrossFireX supposedly does what you are thinking about. From their website:
 
" ATI Hybrid Graphics allows both an AMD 780 Chipset graphics processor and a discrete graphics processor to communicate and work co-operatively yet independent of each other on an AMD-based system to help provide better performance, productivity and power efficiency. Additionally, in systems operating under Windows Vista®, ATI Hybrid Graphics can provide the ability for an integrated graphics processor and a discrete graphics processor to work simultaneously for high performance or dynamically for additional power savings. "
 
I think Gigabyte has a motherboard that supports this, the GA-MA78GM-S2H
 
Haven't tried it so don't know if it's actually working or in one of those "wait for the next set of drivers" stage.

What I think I'll do from now is have two computers: one for internet browsing and general fannying around, and one for gaming. I'll make it so that one of them only uses 100W at most, and the other one will be a 500W beast... A bit of an old school solution, but it will work.

im kinda surprised that nvidia does not have card that under clock its self like processors lower the multiplier. one 8600gt is way more then you would need for surfing the internet. i think nvidia would want to do something like underclocking the card while the system is idle to save power, heat, and have the video cards life extended. i would like to keep my computer on at night but my video card is so hot that it makes my room hot.

I hope this is true :
 
http://www.fudzilla.com/index.php? [...] &Itemid=65
 
Looks very promissing...